Cyrillic symbols support

Hey, I want to add cyrillic symbols support, but I have some questions.

* Is it needed?
* How should I implement it?

Now I use custom formatCharacters for that and I have two variants.

* 'Я' - cyrillic and latin symbols,
* 'Ё' - only cyrillic symbols.

I think it would be nice to add cyrillic symbols to `a` and `A` patterns. Thats very easy.

For example, I use this pattern `/[А-Яа-яЁёA-Za-z]/`. Guys from another cultures can add some additional symbols in it.